Conventional stringed instruments include cellos, violas, violins, guitars, ukuleles and the like. They generate sound through resonance of strings and an acoustic box. The tension of the strings directly affects the intonation.
Please refer to FIGS. 1 and 2 for a conventional adjustment apparatus for tuning the tone of the stringed instruments. It is installed on a head 1 and includes a tuning peg 2, a pintle 3, a string holder 4, a holding ring 5, a clamp ring 6 and a plurality of anti-slip washers 7. The pintle 3 runs through the head 1. The holding ring 5 and clamp ring 6 run through the pintle 3 from two sides of the head 1 and fixedly couple on the head 1. The string holder 4 is fixedly mounted onto one end of the pintle 3 close to the holding ring 5, and the tuning peg 2 is fixedly coupled on another end thereof. The anti-slip washers 7 are run through by the pintle 3 and interposed between the tuning peg 2 and clamp ring 6. The tuning peg 2 presses the anti-slip washers 7 to compress the clamp ring 6 to fix together. The string holder 4 and holding ring 5 may also be interposed by the anti-slip washers 7 to increase anti-slip forces.
The string holder 4 allows a string 8 to fasten thereon. By turning the tuning peg 2, the pintle 3 is driven to drive the string holder 4 to turn, thereby the length of the string 8 can be changed to adjust the tension thereof to further alter the tone to meet performance requirements.
The string holder 4 is threaded through by a string 8. Turning the tuning peg 2, the pintle 3 is driven to turn the string holder 4, thereby the length of the string 8 can be changed to adjust the tension of the string 8, and thus the tone of the string 8 also can be changed to meet performance requirement.
In the conventional string compact adjustment apparatus, the tuning peg 2 and clamp ring 6 are held together merely via frictional force generated by contact between the anti-slip washers 7. When the string 8 is played to generate vibration, the conventional holding structure set forth above cannot prevent the tuning peg 2 from turning reversely and slowly. As a result, the tuning peg 2 gradually loosens and the timber changes during the performance. It cannot meet performance requirement.